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1.
The aim of this study was to establish the feasibility, evaluate the response rate, and assess the impact on local control and survival in locally advanced (bulky nodal) squamous cell carcinoma of the head and neck (SCCHN) patients treated with neoadjuvant chemotherapy consisting of cisplatin followed by continuous infusion of vindesine and fluorouracil with intermittent i.v. folinic acid. Eligibility criteria included histologically proven SCCHN, previously untreated locally advanced stage III-IV with measurable or evaluable disease, no distant metastases, an Eastern Cooperative Oncology Group (ECOG) performance status of less than 2, patient age of at least 18 years, and adequate bone marrow, hepatic, and renal functions. The protocol consisted of three cycles (day 1, day 21, day 42) of Cisplatin (CDDP) 100 mg/m2/day i.v. on day 1 immediately followed by 4 days (96 h) of continuous infusion of vindesine 0.8 mg/m2/day and 5-fluorouracil (5-FU) 600-700 mg/m2/day with folinic acid 150 mg/m2 i.v. every 6 h x 16 doses before locoregional treatment with radiotherapy preceded by radical surgery when appropriate. Twenty-nine patients were enrolled in this study, and 28 were evaluable for activity; an objective response rate of 55% (four complete responses, 12 partial responses) was achieved. Leukopenia and mucositis were the most frequent and severe toxicities. The addition of vindesine did not improve the activity of the CDDP-FU-folinic acid combination, but this may be partly because of the particularly poor prognosis of the present patient population, with 75% of stage IV bulky nodal disease (N2c-N3).  相似文献   
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Multimedia Tools and Applications - Prostate cancer (PCa) has become the second most dreadful cancer in men after lung cancer. Traditional approaches used for treatment of PCa were manual, time...  相似文献   
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We introduce the concert (or cafeteria) queueing problem: A finite but large number of customers arrive into a queueing system that starts service at a specified opening time. Each customer is free to choose her arrival time (before or after opening time), and is interested in early service completion with minimal wait. These goals are captured by a cost function which is additive and linear in the waiting time and service completion time, with coefficients that may be class dependent. We consider a fluid model of this system, which is motivated as the fluid-scale limit of the stochastic system. In the fluid setting, we explicitly identify the unique Nash-equilibrium arrival profile for each class of customers. Our structural results imply that, in equilibrium, the arrival rate is increasing up until the closing time where all customers are served. Furthermore, the waiting queue is maximal at the opening time, and monotonically decreases thereafter. In the simple single class setting, we show that the price of anarchy (PoA, the efficiency loss relative to the socially optimal solution) is exactly two, while in the multi-class setting we develop tight upper and lower bounds on the PoA. In addition, we consider several mechanisms that may be used to reduce the PoA. The proposed model may explain queueing phenomena in diverse settings that involve a pre-assigned opening time.  相似文献   
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The effects and interactions of heating temperature (60 °C to 73.9 °C), salt (0.0 % to 4.5 %?w/v), sodium pyrophosphate (0.0 % to 0.5 %?w/v), and sodium lactate (0.0 % to 4.5 %?w/v) on the heat resistance of a five-strain mixture of Listeria monocytogenes in 75 % lean ground beef were examined. Meat samples in sterile filtered stomacher bags were heated in a temperature controlled waterbath to determine thermal death times. The recovery medium was tryptic soy agar supplemented with 0.6 % yeast extract and 1 % sodium pyruvate. Weibull survival functions were employed to model the primary survival curves. Then, survival curve-specific estimated parameter values obtained from the Weibull model were used for determining a secondary model. The results indicate that temperature and salt have a large impact on the inactivation kinetics of L. monocytogenes, while sodium lactate (NaL) has an impact in the presence of salt. The model presented in this paper for predicting inactivation of L. monocytogenes can be used as an aid in designing lethality treatments meant to control the presence of this pathogen in ready-to-eat products.  相似文献   
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Vegetative cells of Clostridium perfringens enterotoxigenic strains NCTC 8679, NCTC 8238. and H6 were grown at 37 degrees C followed by a 60-min exposure to 28 degrees C or 46 degrees C. D10-values, as a measure of thermal resistance at 60 degrees C, were significantly lower for 28 degrees C exposures as compared with cultures given 37 and 46 degrees C exposures. Following refrigeration at 4 degrees C for 24 h, D10-values for the 37 and 46 degrees C samples could not be differentiated from 28 degrees C samples. Western immunoblot analyses of lysates from heat-adapted cells also detected the increased expression of proteins reacting with antiserum directed against the molecular chaperonins from Escherichia coli; GroEL, DnaJ, and the small acid soluble protein from Bacillus subtilis, SspC. Differential scanning calorimetry (DSC) identified thermal transitions corresponding to ribosomal protein denaturations at 72.1 +/- 0.5 degrees C. Any cellular heat adaptations in the DSC profiles were lost following refrigeration for several days to simulate minimally processed food storage conditions. Further analyses of high-speed pellets from crude cell extract fractions using two-dimensional gel electrophoresis detected the differential gene expression of at least four major proteins in heat-adapted vegetative cells of C. perfringens. N-terminal amino acid analyses identified two of the proteins as glyceraldehyde 3-phosphate dehydrogenase and rubrerythrin. Both appear to have roles in this anaerobe under stressful conditions.  相似文献   
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ABSTRACT: The heat resistance of 35 Salmonella strains was determined at 55 to 65°C. No correlation between the heat resistance and the origin of the Salmonella spp. could be established. D-values in chicken broth, using a linear regression, of an 8 Salmonella serotype cocktail were 4.87, 2.72, 1.30, and 0.41 min at 55, 58, 60 and 62°C, respectively. Using a linear model, the D-values ranged from 4.86 min at 55°C to 0.38 min at 62°C. When the 8 Salmonella serotype cocktail was heated in meat, D-values at the common test temperatures of 58 and 60°C calculated by both approaches were significantly higher (p < 0.05) than those observed in chicken broth.  相似文献   
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In the present investigation, the polycrystalline films of Cd X Zn1–X S were prepared using a sintering technique. We coated slurry consisting of CdS, ZnS in the desired proportion—CdCl2 (as adhesive) and ethylene glycol (as binder)—onto the glass substrates. The films were sintered at a range of temperatures in air atmosphere for the optimization of sintering temperatures using reflection spectroscopy. It was noticed that below 500°C, CdS-dominated films were obtained, and above 500°C, ZnS-dominated films were obtained. The films of desired composition giving appropriate results are obtained at 500°C. The reason is easily understood through reflection spectroscopic studies. Thus, we found 500°C to be the optimum sintering temperature and 10 min was the proper sintering time.  相似文献   
10.
Inhibition of Clostridium perfringens germination and outgrowth by salts of organic acids such as sodium lactate, sodium acetate, buffered sodium citrate and buffered sodium citrate supplemented with sodium diacetate was evaluated during continuous chilling of ground turkey. Turkey breast meat was injected with a brine-containing NaCl, potato starch and potassium tetra pyrophosphate to yield final in-product concentrations of 0.85%, 0.25% and 0.20%, respectively. The meat was ground, mixed with either sodium lactate (1%, 2%, 3% or 4%), sodium acetate (1% or 2%), buffered sodium citrate (Ional, 1%) or buffered sodium citrate supplemented with sodium diacetate (Ional Plus trade mark, 1%), in addition to a control that did not contain added antimicrobials. Each product was mixed with a three-strain C. perfringens spore cocktail to obtain final spore concentrations of ca. 2.8 log10 spores/g. Inoculated products (10 g) were packaged into cook-in-bags (2 x 3 in.), vacuum sealed, cooked at 60 degrees C for 1 h, and subsequently chilled from 54.4 to 7.2 degrees C in 15, 18 and 21 h following exponential chilling rates. Products were sampled immediately after cooking and then after chilling. Chilling of cooked turkey following 15, 18 and 21 h chill rates resulted in germination and outgrowth of C. perfringens spores to 6.6, 7.58 and 7.95 log10 CFU/g populations, respectively, from initial spore populations of ca. 2.80 log10 CFU/g. Incorporation of sodium lactate (1%), sodium acetate (1%), Ional or Ional Plus (1%) substantially inhibited germination and outgrowth of C. perfringens spores compared to controls. Final C. perfringens total populations of 3.12, 3.10, 2.38 and 2.92 log10 CFU/g, respectively, were observed following a 15-h exponential chill rate. Similar inhibitory effects were observed for 18 and 21 chill rates with the antimicrobials at 1% concentrations. While sodium lactate and sodium acetate concentrations of 1% were sufficient to control C. perfringens germination and outgrowth (<1.0 log10 CFU/g growth) following 15 h chill rates, higher concentrations were required for 18 and 21 h chill rates. Ional at 1% concentration was effective in inhibiting germination and outgrowth to <1.0 log10 CFU/g of C. perfringens for all three chill rates (15, 18 and 21 h) tested. Use of sodium salts of organic acids in formulation of ready-to-eat meat products can reduce the risk of C. perfringens spore germination and outgrowth during chilling.  相似文献   
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